Technical Abstract:
This manuscript is part of a series of manuscripts that characterize cotton gin emissions from the standpoint of stack sampling. The impetus behind this project was the urgent need to collect additional cotton gin emissions data to address current regulatory issues. A key component of this study was focused on EPA PM10 emission factors. EPA AP-42 emission factors are generally assigned a rating that is used to assess the quality of the data being referenced. The ratings can range from A (Excellent) to E (Poor). EPA current PM10 emission factor quality ratings for cotton gins are extremely low. Cotton gin data received these low ratings because it was collected almost exclusively from a single geographical region. The objective for this study was to collect additional PM10 emission factor data, based on Method 201A, the EPA-approved stack sampling methodology, for 2nd stage seed-cotton cleaning systems from cotton gins located in regions across the Cotton Belt. The project plan included sampling seven cotton gins across the Cotton Belt. Key factors for selecting specific cotton gins included: 1) facility location (geographically diverse), 2) industry representative production capacity, 3) typical processing systems, and 4) equipped with properly designed and maintained 1D3D cyclones. Five of the seven gins were equipped with 2nd stage seed-cotton cleaning systems. In terms of capacity, the five gins were typical of the industry, averaging 32.6 bales/hr during testing. The system emission factors for PM10 and total particulate were 0.039 kg/bale (0.087 lb/bale) and 0.056 kg/bale (0.123 lb/bale), respectively. The PM10 emission rate from test averages ranged from 0.41 to 1.80 kg/hr (0.90 to 3.96 lb/hr). The ratio of PM10 to total particulate was 70.3%.